scanner-manual.ino

// SPDX-FileCopyrightText: 2023 Carter Nelson for Adafruit Industries
//
// SPDX-License-Identifier: MIT
// --------------------------------------
// i2c_scanner
//
// Modified from https://playground.arduino.cc/Main/I2cScanner/
// --------------------------------------

#include <Wire.h>

// Set I2C bus to use: Wire, Wire1, etc.
#define WIRE Wire

void setup() {
  pinMode(D8, OUTPUT);
  delay(250);

  digitalWrite(D8, HIGH);
  WIRE.begin();
  digitalWrite(D8,LOW);

  Serial.begin(9600);
  while (!Serial)
     delay(10);
  Serial.println("\nI2C Scannerr");
}

const int RST_PIN = D8;  // change to your reset pin
const unsigned long RST_HOLD_MS = 20;   // hold reset low this long
const unsigned long POST_RST_MS = 120;  // wait after release

void manualResetDisplay() {
  pinMode(RST_PIN, OUTPUT);
  // assert reset (active low)
  digitalWrite(RST_PIN, LOW);
  delay(RST_HOLD_MS);
  // release reset
  digitalWrite(RST_PIN, HIGH);
  // give the display time to initialize
  delay(POST_RST_MS);
}

void loop() {
  byte error, address;
  int nDevices;

  Serial.println("Scanning...");

  nDevices = 0;
  for(address = 1; address < 127; address++ )
  {
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    manualResetDisplay();
    WIRE.beginTransmission(address);
    error = WIRE.endTransmission();

    if (error == 0)
    {
      Serial.print("I2C device found at address 0x");
      if (address<16)
        Serial.print("0");
      Serial.print(address,HEX);
      Serial.println("  !");

      nDevices++;
    }
    else if (error==4)
    {
      Serial.print("Unknown error at address 0x");
      if (address<16)
        Serial.print("0");
      Serial.println(address,HEX);
    }
  }
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("done\n");

  delay(5000);           // wait 5 seconds for next scan
}